Field of the Invention
The present invention relates to a laser processing apparatus.
Description of the Related Art
There has been known a processing method wherein a laser beam is applied by a laser processing apparatus to a semiconductor wafer having a plurality of devices such as integrated circuits (ICs) formed thereon (hereinafter referred to simply as “wafer”), to form modified layers along division lines (streets), and, with the modified layers as start points of breakage (splitting), the wafer is divided into individual device chips. The laser processing apparatus is capable of forming an intermittent modified layer by switching application of the laser beam and stopping of the application. Therefore, the laser processing apparatus is capable of processing a wafer having discontinuous division lines (see, for example, Japanese Patent Laid-open Nos. 2010-123723 and 2015-020177).